Jannitti E, Nicolosi P, Tondello G
Opt Lett. 1979 Jun 1;4(6):187-9. doi: 10.1364/ol.4.000187.
A stigmatic spectrograph composed of a toroidal mirror and a concave grating both working at grazing incidence has been built and applied to the observation of laser-produced plasmas. Spatial resolution of 20-30 microm over a region of 1-mm extension and spectral resolution of approximately 1500 have been obtained with a considerable increase in speed of the spectrograph. By varying the relative positions of the optical elements, it is possible to change the wavelength of stigmatic condition in the range 10-300 A. Examples of observations of a beryllium plasma are shown.
